Norbornadiene metal compounds and process for same



United States Patent 3,195,084 NURBORNADENE METAL COMPOUNDS AND PROCESSFOR SAME Geoffrey Wilkinson, London, England, assignor to EthylCorporation, New York, N.Y., a corporation of Virginia No Drawing. FiledOct. 7, 1960, Ser. No. 61,160 11 Claims. (Cl. 26042.9)

This invention relates to norbornadiene-transition metal compounds ofthe metals of group VIII and IB of the periodic table. This inventionalso relates to the preparation of these compounds by reaction ofnorbonadiene and a salt of a group VII-1B transition metal.

An object of this invention is to provide norbonadienetransition metalcomplexes of the metals of group VIII-IB of the periodic table. Afurther object is to provide a method for preparing these compounds byreacting a group VIII-1B transition metal salt with norbornadiene or anorbornadiene derivative. Further objects will become apparent from areading of the specification and claims which follow.

The compounds of my invention are of three general types. The first typeof compound can be termed a 1:1 complex which contains one mole of anorbornadiene compound and one mole of a transition metal salt. Thesecompounds are formed by reaction of a transition metal salt of the ironsub-group e.g. iron, ruthenium and osmium or the nickel sub-group, e.g.,nickel, palladium and platinum with a norbornadiene compound. A furthertype of compound within the scope of my invention may be termed abis(1:1) compound. These compounds are dimeric and are formed byreaction of one mole of a norbornadiene compound with one mole of atransition metal salt. The metals of the cobalt sub-group of theperiodic table, e.g., cobalt, rhodium and iridium form such compounds. Astill further type of compound within the general scope of my inventionmay be termed 1:2 compounds indicating that the compounds contain onemole of a norbornadiene compound and two moles of a transition metalsalt. The metal salts of group IB metals, e.g., copper, silver and gold,react with norbornadiene to form such compounds.

lThe compounds of the invention are, in general, stable organometalliccompounds. They are diarnagnetic and have a number of utilities. Ingeneral, the compounds contain a relatively high quantity of metal permolecule and therefore are excellent sources of the metal for use inchemical processes.

Many of the compounds may be used as fuel additives to residual anddistillate fuels such as those employed in home heater fuels, dieselfuels, and jet fuels. In this use, the additive serves to reduce smokeand/ or soot formation on combustion of the fuel. Further, my compoundsmay be added to hydrocarbon fuels of the gasoline boiling range for usein an internal combustion engine. In this use, my compounds act as anantiknock agent. In addition, many of my compounds are useful additivesto various hydrocarbon lubricants to improve their lubricity. Anotheruse for my compounds is as a metal source in gas phase metal plating. Astill further use for my compounds is as additives to solid propellantsto control burning rate.

The norbornadiene compound (a hydrocarbon containing abicyclo(2:2:l)-hepta-2:5-diene ring) which isa reactant in my processmay be substituted with hydrogen or hydrocarbon substituents such asalkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups,alkaryl groups and aralkyl groups. Preferably, the norbornadienereactants which I employ contain from 7 to about carbon atoms. Thesimplest norbornadiene which I employ is the compoundbicyclo(2:2:l)-hepta-2:5-diene.

Patented Sept. 24, 1963 Similar compounds which may be employed aremethyl bicyclo(2:2:l)-hepta-2:5-diene, phenyl bicyclo(2:2:l)-hepta-2z5-diene, benzyl bicyclo (2:2:1)-hepta-2:5-diene, tolylbicyclo(2:2:l)-hepta-2:5-diene, butenyl bicyclo-(2z2:1)-hepta-2:5-diene,' and the like.

The transition metal saltswhich are the other reactant in my process aresalts of the group VIII-1B transition metals which preferably aresoluble to some degree in polar solvents. Typical of such salts are thecyanides, halides, nitrates, sulfates, acetates, phosphates, phosphites,and the like. Preferred transition metal salts which are employed in myprocess are the transition metal halides of the group VIIIIB metals.

My process comprises the mixing together of the norbornadiene compoundand a group VIII-1B transition metal salt, both as defined above.customarily a solvent is employed although the nature of the solvent isnot critical. The preferred solvents are polar in nature such as water,ethanol, ether, chloroform, and the like. The temperature and pressureemployed in the reaction are not critical and the process goes well atroom temperature and atmospheric pressure. Agitation of the reactionmixture may be employed although this is not necessary. In some cases,the process can be carried out under a blanketing atmosphere of an inertgas which protects both the reactants and products from oxidation. 7Since the products obtained from my process are generally solids, themeans employed for separation of product involve crystallization,filtration, etc. In other words, the products can be separated by thecustomary methods employed to separate solid products from a generallyliquid reaction medium.

To further illustrate the compounds of the invention and their mode ofpreparation, there are presented the following examples in which allparts and percentages are by weight unless otherwise indicated.

Example I To 2.82 parts of norbornadiene were added 1.36 parts of silvernitrate in 10 parts of water. The mixture was agitated at roomtemperature for five minutes, and the white solid complex which formedwas filtered off and recrystallized from ethanol to give 0.95 parts ofnorbornadiene-bis(-silver nitrate). Analysis: Found: C, 19.4; H, 2.4;Ag, 50.2. C I-I (AgNO requires: C, 19.5; H, 1.9; Ag, 50.0 percent.Norbornadiene-bis(silver nitrate) decomposes in water giving off astrong smell of norbornadiene. The compound also decomposes on standingin the air or on warming. It is soluble in warm ethanol, carbontetrachloride, chloroform and benzene, but it is almost insoluble inacetone, ether and light petroleum.

Example 11 To 2.6 parts of cupric bromide in 23.7 parts of ethanol wasadded 4.55 parts of norbornadiene. The mixture was agitated for fiveminutes. The white crystalline product formed was removed by filtrationand washed with 3.94 parts of ethanol and 3.52 parts of ether to give1.4 parts of norbornadiene-bis(cuprous bromide). Found: C, 19.8; H, 2.6and Cu, 32.8. C H (CuBr) requires: C, 22.2; H, 2.1 and Cu, 33.5 percent.The compound remained as a fine, White crystalline solid which slowlyturned green on standing in air. The compound readily lost norbornadieneat reduced pressure to leave cuprous bromide, and was decomposed inwater to give cuprous oxide. Norbornadiene-bis(cuprous bromide) ispractically insoluble in all common organic solvents.

Example III To 1.82 parts of norbornadiene were added one part ofplatinic chloride and 10.5 parts of glacial acetic acid. The reactionmixture was agitated for 15 minutes after which a brown solid whichformed was filtered oil and ethanol.

fine, white crystals which decomposed at a temperature between 230-280C. and were somewhat soluble in acetic acid, chloroform and acetone.

Example IV To 1.1 parts of dibenzonitrile palladium dichloride in 52.5parts of chloroform were added 3.64 parts of norbornadiene. The mixturewas allowed to stand for one hour after which the yellow deposit formedwas filtered oh and washed with chloroform and light petroleum. Afterrecrystallization from glacial acetic acid, the product was washed withmethanol and acetone and vacuum dried to give 0.58 parts ofnorbornadiene palladium dichloride. Found: C, 31.4 and H, 3.6. CqHgPdClzrequires: C, 31.2 and H, 3.0 percent. The compound was obtained asyellow needles which decomposed at temperatures between 190-200 C.

Using a procedure similar to that employed in Examples III and IV, theproduct methyl norbornadiene-nickel dichloride is prepared in goodyield.

Example V To 1.03 parts of ruthenium trichloride (a commercial mixtureof hydrated triand tetra-chlorides) was added 31.6 parts of ethanol toform a solution which was centrifuged to remove insoluble material. Theclear redbrown solution was shaken with 3.64 parts of norbornadiene andallowed to stand for 25 hours. The red product was washed repeatedlywith acetone to remove ruthenium chlorides. There was obtained 0.6 partsof norbornadiene ruthenium dichloride. Found: C, 31.6; H, 3.9 and Cl,27.5. C H RuCl requires: C, 31.8; H, 3.1 and Cl, 26.8 percent. Thecompound was diamagnetic and insoluble in water and all common organicsolvents.

Example VI To 1.1 parts of ruthenium chloride, as defined in theprevious example, was added 31.7 parts of acetone to form a solution.The solution was centrifuged to remove any insoluble material. To theclear solution was added four parts of lithium bromide, and theresulting solution was filtered and added to 3.64 parts of norbornadieneand allowed to stand for 24 hours. The precipitate was washed repeatedlywith acetone and then vacuum dried to give 0.6 parts of nor-bornadieneruthenium dibromide. Found: C, 23.2 and H, 2.8. CqHgRUBI'z requires: C,23.8 and H, 2.3 percent. The compound was a darkbrown solid which isinsoluble in all common solvents.

The products butyl norbornadiene iron dichloride and nor'oornadieneosmium dibromide are prepared in good yield according to the procedureemployed in Examples V and VI by reaction of butyl norbornadiene withferric chloride and the reaction of norbornadiene with osmiumtribromide.

Example VII To 0.7 parts of rhodium trichloride (commercial mixture ofhydrated triand tetra-chlorides) was added 1.82 parts of norbornadienein about 8 parts of aqueous The mixture was agitated for two days. Theyellow deposit which formed was recrystallized from hot chloroform/lightpetroleum to give 0.62 part of norbornadiene rhodium chloride whichdecomposed at 240 C. Found: C, 37.3; H, 3.7; Rh, 45.3; C1, 15.5 percentwith a molecular weight of 481 (ebullioscopic in benzene). (C7H3RhC1)2requires: C, 36.5; H, 3.5; Rh, 44.6; C1, 15.4 percent with a molecularweight of 462. The compound forms as fine-yellow crystals which aresoluble in chloroform and benzene but are almost insoluble in ether andlight petroleum.

dib-romide and p-toluidine.

By a similar process to that employed in Example VII, 7

dimeric compounds containing the basic structural-unit norbornadienecobalt chloride and norbornadiene iridium bromide are prepared in goodyield.

The compounds of my invention may be employed in various chemicalreactions with nitrogen-containing compounds such as pyridine tandp-toluidine. This use is illustrated by means of the following ExamplesVIII and 1 IX in which all parts and percentages are by weight unlessotherwise indicated.

Example VIII To 0.39 parts of norbornadiene ruthenium dichloride,prepared as in Example V, was added 14.75 parts of pyridine, and theresulting mixture was heated at 120 C. for 45 minutes. On cooling, theresultant red solution gave a red crystalline product. Recrystallizationfrom chloroform/ light petroleum gave 0.3 parts of tetrapyridineruthenium dichloride. Found: C, 49.4; H, 4.3; N, 11.4; C1, 14.8 percentwith a molecular weight of 487 (ebullioscopic in benzene). Calculatedfor C H Cl N Ru: C, 49.1; H, 4.3; N, 11.5; C1, 14.5 percent and amolecular weight of 489. a

Example IX To 0.29 parts of norbornadiene ruthenium dichloride, preparedas in Example V, was added 0.8 parts of p-toluidine. The mixture wasfused and held at a temperature of C. for 30 minutes. After beingcooled, the red solid residue was washed with ether and dichloromethaneto yield a yellow crystalline solid which, on vacuum drying, gavenoroornadiene-bis(p-toluidine) ruthenium dichloride (0.2 parts). Found:C, 53.1; H, 5.4; N, 6.2 and Cl, 14.7. C H N Cl Ru requires: C, 52.6; H,5.5; N, 5.9 and Cl, 14.8 percent. The compound is insoluble inchloroform.

In a similar manner to that employed in Example IX, the compound,norbornadiene-bis(p-toluidine) ruthenium dibromide, was prepared fromnorbornadiene ruthenium Found: C, 45.0; H, 5.1; N, and BI, 27.9.C21N25N2BI'2RH requires: C, H, 4.6; N, 4.9 and Br, 28.2 percent.

The compounds of the invention have a variety of uses. Many, forexample, are useful as additives to hydrocarbon fuels and lubricants.For example, many of them, when added to a hydrocarbon fuel of thegasoline boiling range, are found to increase the octane number of thefuel. The compounds may be added to gasoline along with halo'hydrocarbonscavengers such as ethylene dichloride and ethylene dibromide,phosphorus ignition control compounds such as tricresyl phosphate, andother antiknock agents such as tetrethyllead, methylcyclopentadienylmanganese tricarbonyl andthe like. They are also useful as additives tojet fuels, home heater fuels and diesel fuels to reduce smoke and/ orsoot formation on combustion of the fuels. In addition, my compounds maybe employed as additives to lubricating oils to improve theircharacteristics. A still further utility for my compounds is asadditives to solid propellants to control the burning rate of thepropellant.

The compounds may also be used as metal plating agents. When soemployed, they are decomposed at elevated temperatures so as to lay downa metallic film on a substrate material. Preferably, the platingoperation is carried out in the presence of an inert gas so as toprevent oxidation of the metal coating or substrate material during theplating operation. The metal films, for example, may be employed toproduce a decorative efiect on the substrate material, to increase itsresistance to corrosion, and to form a conductive surface. In the latterapplication, the compounds can be employed in forming printed circuitsby decomposing the organometallic compound so that it lays down anelectrically conductive metallic film on a substrate surface that iscovered by a stencil.

Deposition of metal on a glass 'cloth illustrates my process whichemploys the compounds of the invention in gas phase metal plating. Aglass cloth band weighing one gram is dried for one hour in an oven at150 C. It is then placed in a tube which is devoid of air and there isadded to the tube 0.5 grams of norbornadiene ruthenium dibromide. Thetube is heated at 400 C. for one hour after which time it is cooled andopened. The cloth has a uniform metallic grey appearance and exhibits again in weight of about 0.02 gram. Thus a cloth is prepared in which theindividual fibers are coated with a layer of ruthenium.

Having described my novel compounds, their mode of preparation and theirmany utilities, I desire to be limited only within the lawful scope ofthe appended claims.

I claim:

1. Compounds containing 1 mole of a norbornadiene hydrocarbon compoundcontaining from 7 to about 15 carbon atoms, said norbornadiene compoundbeing bonded to a transition metal salt selected from the classconsisting of inorganic iron-subgroup metal halides and nitrates andinorganic nickel-subgroup metal halides and nitrates.

2. Dimeric compounds containing as the basic unit one mole of anorbornadiene hydrocarbon compound bonded to one mole of a salt, saidnorbornadiene compound containing from 7 to about 15 carbon atoms andsaid salt being selected from the class consisting of inorganiccobalt-subgroup metal halides and nitrates.

. Norbornadiene platinum dichloride.

. Norbornadiene palladium dichloride.

. Norbornadiene ruthenium dichloride.

. Norbornadiene ruthenium :dibromide.

. Noribornadiene rhodium chloride dimer.

Process comprising reacting a norbornadiene hydrocarbon compoundcont-aining from 7 to about 15 carbon atoms with a salt selected fromthe class consisting of inorganic group VIII metal halides and nitratesand dibenzonitrile group VIII metal halides.

9. Process for the preparation of norbornadiene platinum dichloride,said process comprising reacting norbornadiene with platinic chloride.

10. Process for the preparation of norbornadiene palladium dichloride,said process comprising reacting dibenzoni-trile palladium dichloridewith norbornadiene.

11. Process for the preparation of nor-bornadiene ruthenium dibromide,said process comprising reacting ruthenium dibromide with norbornadiene.

References Cited in the file of this patent Alexander et al.: J.A.C.S.,82 (Feb. 5, 1960), pp. I

Traynham et al.: J.A.C.S., 81 (Feb. 5, 1959), pp. 571-574.

1. COMPOUNDS CONTAINING 1 MOLE OF A NORBORNADIENE HYDROCARBON COMPOUNDCONTAINING FROM 7 TO ABOUT 15 CARBON ATOMS, SAID NORBORNADIENE COMPOUNDBEINF BONDED TO A TRANSITION METAL SALT SELCTED FROM THE CLASSCONSISTING OF INORGANIC IRON-SUBGROUP METAL HALIDES AND NITATES ANDINOGANIC NICKEL-SUBGROUP METAL HALIDES AND NITRATES.